The present invention relates to an incombustible material produced with the use of mineral substances and to a method for producing it.
Board-shaped structural elements of gypsum, asbestos and cement, those composed of gypsum being reserved for interior use, are used in construction in ever increasing quantities. One reason for this is that the presently preferred light-weight construction methods require such structural elements.
However, the prior art materials leave much to be desired regarding their physical characteristics, in that, for example, they tend to absorb an unduly large amount of water, and to swell to a considerable degree, they are difficult to process and have insufficient strength. The rigid compression bond between the component materials here determines the relatively low bending strength of the structural elements produced therefrom. On the other hand, structural elements containing such mineral components produced according to DIN [German Industrial Standard] 4102 are completely or almost completely incombustible.
In the desire to produce board-shaped structural elements with improved physical properties, cement-bound wood chip boards and gypsum fiber boards have been developed which for the most part fall into the category of completely or almost completely incombustible construction materials.
It is also known to construct synthetic resin bound wood chip board materials which attain extremely high physical strength values by virtue of their defined chip shape and the elastic synthetic resin bond. The water absorption and swelling of such materials can thus be influenced by the selection of certain resins and additives. With respect to the burn behavior of such wood chip materials, there already exist a series of methods to provide these materials with flame protection. Therefore, some of these wood chip materials also satisfy the requirements for incombustible construction materials according to DIN 4102.
Construction materials made of fibrous, granular or flaky mineral substances, such as asbestos, mica and vermiculite, are also known. In order to improve the bond with the synthetic resin, fine wood chips have sometimes also been added to these materials. Since the mineral raw materials themselves are imcombustible, but do not actuate any flame or fire inhibiting reactions in the case of fire, only the amount of organic substances contained in these materials determines their classification as combustible or incombustible substances according to DIN 4102. It must, however, be considered, that the mineral raw materials contribute only very slightly to the physical strength of a product by their already mentioned compressive bond so that purely mineral building materials can be used only within limits.